Forging head



Sept. 25, 1934. G. K. GARRETT FORG I NG HEAD Filed Jan; 5, 1933 4 Sheets-Sheet 1 INVENTOR am'gaif (/mvzfi,

Sept. 25, 1934; e. K. GARRETI:

. FORGING HETADI Filed Jan. 5. 1933 4 Sheets-Sheet 2 INVENTOIR: (2011,10 K (jar/M11 ATTORNEYS.

u Sept. 25, 1934. G. K. GA RRE'i'T FORGING HEAD Filed Jan. 5. 1953 4 Sheets-Sheet 4 I INVEN/TOR: A 29 K WITNESSES:

TTORNEY Patented Sept, 25, 1934 UNITED STATES PATENT OFFICE 1.9mm rename mean George K. Garrett, Bryn Mawr, Pa. v Application January 5.19:3, Serial No. $50,220

' 11 Claims (01. 80-34 This invention is concerned with apparatus for forging bar stock or drawing wire into a product having an irregular cross section, for example,

-material of trapezoidal or wedge-like section suitable for the manufacture of split lock washers and the like.

Considered from the broadest aspect, my invention is directed toward enabling drawing or forging of metallic bar stock or wire into a product having a consistently uniform but irregular cross section by a single pass between a group of forging rolls.

A further object of my invention is to make it possible, through a novel relative disposal of the forging rolls in a forging head, to varythe size of the opening afforded between said rolls for drawing or forging correspondingly larger or smaller cross sectional areas with attendant preclusion of "fins or other product.

In connection with forging heads of the kind specifically referred to, it is another object of my invention to relieve the forging rolls of all strain except for the pressure due to direct contact with the metallic stock passed between them incident to the forging operation.

Still other objects and attendant advantages will become readily apparent from the detailed description following of the attached drawings, wherein Fig. I is a front elevation of a drawing or forging head conveniently embodying my invention in one form,portions of the head having been broken away and shown in section to expose important details of construction.

Fig. II is a view, partly in section and partly in elevation, taken as indicated by the arrows II-II in Fig. I.

Fig. III is a fragmentary detail cross sectional view taken as indicated by the arrows III-III 40 in Fig I.

Fig. IV is a fragmentary view substantially through the medial plane of the head drawn to an enlarged scale; and showing the relation of the contiguous portions of the treads of the forging rolls that jointly define the irregular opening through which the stock is passed incident to being forged or drawn. a

Fig. IVa is a view like Fig. IV with the forging rolls differently adjusted.

Fig. IVb is a similar view showing a somewhat different arrangement of the forging rolls Fig. V is a perspective view of one of the journal blocks for the forging rolls.

Fig. VI is a view corresponding to Fig. I showing a somewhat modified form of my invention.

irregularities in the Fig. VII is a. part side elevation and part crosssectional view taken as indicated by the arrows VII-VII in Fig. VI.

Fig. VIII is a. detail cross sectional view taken as indicated by the arrows VIIIVIII in Fig. VI. 7 Figs. IX and X are detail perspective views respectively of a roll journal block and an associated journal block holder embodied in the orsuch journal block; and I Fig. X1 is a fragmentary perspective view typifying a product such as may be drawn or forged with either form of head. a

In the form delineated in Figs. I-V, the drawing or forging head of my invention comprises a group of radially-arranged forging rolls, whereof there are in the present instance four, respectively designated by the numerals 12, 13, 14 and 15. As shown inFigs. I and IV, the three rolls 12, 13

ganization of Figs VI and VII; and a holder for 66 "and 14 are disposed in i quadrant relation, the mem dial roll 13 of the three having a square tread and the diametrically opposed rolls 12 and 14 having their treads obliqued or beveled somewhat to corresponding degrees. Thus the forging pass sides formed by the bevelled treads of 89 the opposite rolls 12, 14, which diverge away from one another toward the intermediate, included pass side formed by the tread of the intermediate roll 13, crowd the metal passing through the opening over against the intermediate roll tread. As determined by the arrangement of these rolls 12, 13, 14, the forging opening or roll-pass is of a configuration suitably corresponding and adapted to a substantially trapezoidal or wedge-like rolled section,. with divergent opposite sides. The fourth roll 15 which opposes the square-treaded roll 13, is, on the other hand, askew from normal to-the planes of revolution of the rolls 12, 14 between which it forms an intermediate pass side, being off quadrant by an angle corresponding to 95 the tread bevel of the M1112, and has its tread obliqued like said roll 12 and the roll 14. At the roll-pass corners defined by the cooperation of the treads of rolls 12, 13, 14 (and 15), a flatbounding roll tread corner lies directly in front of the adjacent roll tread with which it coacts, and even makes contact therewith. The described arrangement of the rolls 12-14 thus defines an opening or forging pass 16 having the closed configuration of a trapezoid, that is to say,

a quadrilateral figure with two parallel and two counter-inclined sides. As further shown in Figs. I and IV, the side of one roll of the group 12-15 marginally laps the tread of the next adjacent roll, the marginal contact being snug with torily with that of the forging roll.

attendant preclusion of spaces or crevices through which any metal might flow incident to forging of the stock passed through the opening 16: i. e., the corner of each roll coacts with the tread of the adjacent roll, rather thanwith its side, so far as is necessary to obviate formation of fins on the 'stock S dealt with. More particularly, the roll 15 has its side or end face tangent to the tread of the roll 12 along an element of the beveled surface, and the roll 14 is likewise facially tangent to the tread of this roll 15. A similarly snug fit obtains between the tread of the roll 13 and the end or side face of the roll 12, while that between the side of the roll 13 and the tread of the roll 14 is a close point" contact, likewise precluding the formation of fins even on stock S that completely fills the roll pass. I'he planes of revolution of the rolls 12-15 correspond to their tread-engaging side faces.

The forging rolls 12-15 are journalled, with capacity for free rotation, in separate journal blocks 1'7 whereof the inner ends are truncated as shown in Figs. I and IV to enable close inward adjustment of said rollers. In each instance the forging roll is confined between the sides of the narrow portion 18 of alongitudinal slot 19 in the corresponding journal block 17; and each said roll is formedwith trunnions 20 which engage a transverse, notch 21 in the truncated end of its journal block. This construction obviously facilitates placement of the forging rollers in the journal blocks 17 and moreover allows the necessary latitude in the operation of the rolls. The wider portion of the slot 19 in each journal block 17 is occupied by a relatively large thrust-resisting backing roll 22 which contacts peripherally with the forging roll 12, 13, 14 M15, as the case may be, and which hasits tread complementarily beveled or squared: i. e., the backing roll revolves in the same plane as the corresponding forging roll, and its tread angle corresponds compensa- The trunnions 23 of each backing roll 22 are supported in ball bearings '24 set into circular openings 25 (Fig. V) provided for them in opposite sides of the journal block 17. The backing rolls 22 considerably reduce the frictional resistance to passage of stock S through the roll pass, which is of special advantage in rolling fine wire of soft metal, liable to break under heavy draft.

Individually associated with the journal blocks 17 are wedges 26, which, together withsaid journal blocks, are lodged in radial slots 27 of a cruciform frame 28 whereof the arms are designated 29, the block and the wedge being in each instance confined between the back wall 30 of said frame and a keeper plate 31 secured crosswise of the 1 ends of the corresponding frame arm 29 by means of cap screws 32. 'To shift the journal blocks 17 along the slots 2'7 of the frame 28 for the purpose of radially adjusting the forging and backing rolls, in the planes in which they revolve, I have provided in each instance a set screw 33 which takes into the end of the'corresponding arm of said frame and bears against the outer end of the block. Furthermore, to shift the wedges 26 endwise within the slots 27 for the purpose of adjusting the forging and backing rolls sidewise, I have provided separate set screws 34 which, like the set screws 33 aforementioned, take into the ends of the arms of the frame 28 and bear against the outer ends of said wedges. A number of set screws 35 along one side of each arm 29 of the frame 28 serve to hold the corresponding journal block 17 to its wedge 26. By virtue of the aforedescribed provisions it is obviously possible to vary the size of the opening 16 and thereby adapt thehead for roll forging correspondingly smaller or larger sections. In Fig. XI I have illustrated how round bar or wire stock S is converted, by the action of the forging rollers 12-15 set as in Figs. I-IV, into material M of .trapezoidal section corresponding in shape tothe opening 16 between said rolls. As shown, I employ bar or wire stock S having substantially the same cross sectional area as that of the material M which is to be produced. As a consequence, the forging is accomplished smoothly andwithout accumulation or backing of excess metal behind the forging rolls 12-15 such as would be likely to choke or stall the apparatus and prevent uniformity in the product. The close contact of the rolls 12-15 at the regions of overlap obviously precludes crevices through which any displaced metal'mightflow and cause fins or other irregularities in the forged material. During the forging operation it is evident that the backing rolls 22 operate to relieve the forging rolls 12-15 of all strain except that incurred through the direct contact of the treads of said forging rolls with the metal being forged.

In the alternative embodiment of my invention illustrated in Figs. VI-XI the four forgingrolls 12w-15a are considerably larger in diameter as compared with those of the first described embodiment; and the backing rolls are here entirely dispensed with. 'As before, journal blocks 17a with longitudinal slots 19a are used to carry the forging rolls l2ai-l5a, said blocks being in this instance fitted with ball bearings 36 for the trunnions 20a of the rolls. A further departure in q the modification will be noted in the provision of separate holders 3'? to receive the individual journal blocks 17a with capacity for endwise adjustment, one of these holders being illustrated in perspective in Fig. X. As shown, the holders 3'7 are of channel configuration with hollows 38 of a width and depth to snugly receive the journal blocks 17a. (see Fig. VIII) which latter are maintained against outward displacement by retainer plates 39 screw-attached to the frontal edges of the holders. The frame 2801 of the modified forging head is circular as seen in Fig. V1, and affords four radial openings 27a to accommodate the holders 37 with provision for lateral adjustment. At opposite sides, the holders 36 are formed with fianking flanges 40 to lap the frontal face of the frame 2801. at the edges of the radial openings 2711, said flanges havingv transverse slots 41 for passage of securing screws 42. Radial adjustment of the rolls 12w-15a. is effected through the instrumentality of screw bolts 33a engaging boxes 43 or" the frame 28a and bearing against the outer ends of the blocks. Lateral adjustment of the forging rolls 120-1511. is similarly effected by screws 34a. which are rotative in, but held against axial movement in outwardly-projecting clevised bosses 44 of the frame 28a, said screws taking into the sides of the holders 37, see Figs. VI and VIII. By proper adjustment of the screws 33a and 34a it is obviously possible to vary the size of the 1 openings 16a between the contiguous portions of the peripheries of the four forging rolls 120-150, exactly as and for the purpose described in 'connection with the first embodiment. The modified forging head of my invention is particularly adapted for forging high carbon steels, the larger curvatures of the peripheries of the forging rolls 1211-1511. facilitating a more gradual displacement of the metal incident to change of the stock from circular to quadrangular cross section. Due to the absence in this case of backing rolls, the forging rolls 12a-15a are of course obliged to bear all the strain imposed upon them during .the operation of the head.

By employing in connection with'the square treadedroll 13 of the first embodiment of my invention, diflicultly sloped wedges 26, it is possi-' ble to determine a tilt for said roll, for example as shown at 40 in Fig. IVb, thereby to define in conjunction with the other rolls 12, 14 and 15, an irregular quadrangular opening 16b whereof no two sides are equal, for rolling sections of like shape. A similar disposal of the roll 13a in the modified form of my invention illustrated in Figs. VI-VIII may be obtained by'angularlyadjusting the" corresponding holder block 37.

Either form of my improved forging head is thus adaptable to forging not only diiferent sizes of the same quadrangular configuration, but to forging irregular sections of different shapes.

Fig. IVc shows an alternative arrangement wherein the upper roll 13c is beveled like the companion rolls 12c, 14c and 15c and the axis of said roll 130 is set at an angle to correspond with the bevel of the roll 140 which it overlaps. This arrangement insures close contact along the region of overlap between the'rolls13c and 140 but is not suitable for rolling non-parallel sided sections such as described in connection with Fig. IV.

From the foregoing it will be seen that I have provided a roll forging head which is simple in construction, free from liability to easy deranges ment and operable continuously at high speeds.

As hereinbefore stated, the apparatus of my invention is especially advantageous in the production of material for the manufacture of split lock washers where strength, toughness and a high degree of springiness are requisite in the steel. In this connection it may be pointedout' that by roll forging practiced with my invention, an improved grain structure is secured in the metal through compression of the crystals, as compared with material produced by drawing in which case the crystals are distorted and enlarged. Furthermore, to produce, for example, a section x' inches by the drawing method requires three annealings, whereas by roll forging with my apparatus, only one annealing is necessary, so that the possibility of decarbonizing the metal is reduced to the very minimum.

Having thus described my invention, I claim: 9' l. A forging head for producing trapezoidal or wedge-like rolled sections, comprising a group of revolubly mounted flat-tread forging rolls radially arranged with the flat treadsv cooperating as sides to form an irregular'forging opening or roll-pass of multi-angular configuration suitably corresponding and adapted to the rolled section aforesaid, and" with a flat-bounding roll tread corcomprising four forging r'olls radially-arranged ner directly in front of and coacting with the adjacent flat roll tread at the roll-pass corners defined by the cooperation of said roll treads; the roll treads forming two opposite sides of said roll-pass opening diverging away from one another toward an intermediate roll tread forming an intermediate, included side, so as to crowd the metal passing through the opening against said I ating as sides to form an irregular, closed-figured,

multiangular forging opening or pass; twoof said rolls, arranged opposite one another, having their treads diverging, and at least one of the 3. A forging head comprising a group of revolubly mounted forging rolls, in part, at least,

bevelled on their treads, radially arranged with the corner of each roll coacting with the tread of an adjacent roll, and with the treads cooperating as sides to form an irregular, closed-figured, multiangular forging opening or pass; two of said rolls, arranged opposite one another, having their treads diverging, and one at least ofthe rolls whose treads form pass sides intermediate those formed by said opposite rolls revolving and being adjustable in a plane which is askew from normal to the planes of revolution of said opposite rolls and is tangent to the one of said opposite rolls with which its own comer coacts as aforesaid.

4. A forging head comprising a group of revolubly mounted forging rolls, in part, at least, bevelled on their treads, radially arranged with the corner of each roll coacting with the tread of an adjacent roll, and with the treads cooperating as sides to form an irregular, closed-figured, multiangular forging opening or pass; two of said rolls, arranged opposite one another, having their treads diverging, and one at least of the rolls whose treads form pass sides intermediate those formed by said opposite rolls having a bevelled tread tangent to the side face of the one of said opposite rolls whose corner coacts with its said bevelled tread as aforesaid, and revolv least three revolubly mounted forging rolls, in

part, at least, bevelled on their treads, radially arranged with the corner of each roll coacting with the tread of an adjacent roll, and with the treads cooperating as sides toform an irregular,

closed-figured, multiangular forging opening or pass; two of said rolls, arranged opposite one another, having their treads diverging, and at least one of the rolls whose treads form pass sides intermediate those formed by said opposite rolls having its plane of revolution askew from normal to the planes of revolution of said opposite rolls; and backing rolls for said forging rolls revolving in their planes of revolution and of compensatorily corresponding tread angles, whereby friction is reduced.

6.'A forging head for the purpose described in opposing pairs, one such pair having their treads beveled, and one of the rolls of the second pair having a square tread and the other a beveled tread, with attendant formation between the contigous portions of the treads of the four rolls of an irregular quadrangular ,opening with nonparallel sides, for passage of the stock which is' to be forged; g

7. A forging head comprising four radiallyarranged rolls, three of said rolls being spaced in quadrant relation, the medial roll of the three having a square tread and the other two of the three having beveled treads, and thefourth roll being in non-quadrant relation with the others and having its tread beveled and opposing the square tread of the medial roll of the three aforesaid, with attendant formation between the contiguous portions of the treads of the four rolls of an irregular quadrangular opening with two non-parallel'sides, for passage of the stock which is to be forged.

8. A forging head comprising four forging rolls radially arranged in opposing pairs, one such pair having their treads bevelled, and one of the rolls of the second pair having a square tread and the other such rollhaving a bevelled tread to which the side face of one roll of the first pair is tangent, and being tangent on its own side face to the tread of the other roll of the first pair, and also being adjustable and revolving in the plane of such face; said four rolls forming between the contiguous portions of their treads an irregular quadrangular forging opening or pass with nonparallel sides.

9. A forging head comprising a group of four forging rolls radially arranged with portions of their treads in contiguous relation and with a face of one roll marginally overlapping the tread of the next adjacent roll to define an irregular quadrangular opening for passage of the stock which is to be forged, three of said rolls having beveled treads, and the fourth a square tread; and means whereby thesquare treaded forging roll may be angularly adjusted positionally so that no two sides of the opening aforesaid are parallel.

10. A forging head comprising a group of radially-arranged forging rolls withv the contiguous portions of their treads forming an irregular multi-angular opening with non-parallel sides for passage of the stock which is to be forged; a backing roller running in contact with each of the forging rolls to take the thrust of the latter; blocks wherein the respective forging and backing rolls are journalled for independent rotation; a frame with radial slots for lodgment of the journal blocks; and means whereby said blocks may be adjusted along and transversely of the slots in the frame to vary the size of the aforesaid opening.

11. A forging head comprising a group of radially-arranged forging rolls with the contiguous portions of their treads forming an irregular multi-angular opening with non-parallel sides for passage of the stock which is to be forged;

a backing roller running in contact with each of the forging rolls to take the thrust of the latter; blocks wherein the forging and backing rolls are respectively journalled for independent rotation;

a wedge associated with each journal block; a frame with radial-slots for lodgment of the respectively associated journal blocks and wedges; and means whereby the journal blocks and the wedges may be adjusted along the radial slots of the frame to vary the size of the opening between the contiguous tread portions of the forging rolls.

GEORGE fr. GARRETT. 

